1. Field of the Invention
The present invention relates to a method of encapsulating an organic light emitting display device and, more particularly, to a method of encapsulating an organic light emitting device without needing to perform a mask aligning process when coating on a sealant.
2. Description of the Related Art
In general, an organic light emitting display device (OLED) is an emissive device, and thus, has a wide viewing angle and a high contrast ratio. Also, an organic light emitting display device may be manufactured to be slim and light-weight, and has low power consumption since the organic light emitting display device does not require a backlight.
However, the OLED, and electrodes and organic layers included in the OLED, are prone to degrade due to reaction with oxygen and moisture penetrating therein. Therefore, methods of tightly sealing the OLED to prevent the electrodes and organic layers included in the OLED from being exposed to external elements have been researched.
A cap-shaped sealing member having grooves is conventionally formed from a metal can or a glass substrate, and a moisture absorbent for absorbing moisture is loaded on the grooves in a powder form or a film attached to the grooves by using a dual-sided tape. The sealing member is then attached to a substrate on which an OLED is formed by using an ultra violet (UV) hardening sealant or a thermal hardening sealant. However, this method is disadvantageous in terms of high material and process costs due to accompanying manufacturing processes, such as a mask aligning process, when coating on the sealant.
Also, an OLED may be sealed via a film instead of a metal can or a substrate. In this case, however, there is a limit in preventing moisture from penetrating therein, and there is a high possibility of the OLED being damaged during manufacturing and when using it, thereby reducing durability and reliability. Accordingly, it is difficult to mass produce.
In another method, frit may be formed between a lower substrate and an upper substrate. This method may effectively protect an OLED without needing to use a moisture absorbent. However, the method is disadvantageous in view of deformation since frit has poor ductility and malleability characteristics. Therefore, when an OLED having frit is exposed to an external impact, a crack may be generated in the frit. As a result, the frit may become detached from the OLED or the OLED may be damaged.